In order for a drawer to work as intended, there must be some sort of track system upon which the drawer slides within the cabinet when a user pulls or pushes the drawer.
Very generally, there are two basic designs of these systems. The first comprises ridges running along the sides of the drawer that rest upon complementary ridges located on the sides of the cabinet. The second style comprises rails that move against each other along typically wheeled tracks, thereby creating a smoother and steadier user experience.
The first style is often relegated to inexpensive, do-it-yourself, pre-fab furniture and bedroom bureaus. The first style usually does not comprise a stop to prevent the drawer from being pulled completely out of the cabinet, which may only be an annoyance if it results in the occasional spill of clothes, but can be quite dangerous if the drawer contains heavy and sharp kitchen tools. Further, since the first style requires the user to work against dry friction, the usefulness of the first style is diminished if the drawer contains a heavier load such as kitchen tools and flatware.
The second style is more commonly found in kitchen cabinets and other similar cabinets intended to house heavier loads since the wheels provide a smoother motion with greatly decreased friction over the first style, and because this style of track commonly also comprises some manner of stop that prevents a user from accidentally pulling the drawer out too far and causing a drawer of heavier and more dangerous items, e.g., knives and hammers to drop on the user's feet. Common variations of this style include one rail attached to each the cabinet wall and the side of the drawer, and two rails attached to the cabinet walls and clipped to the side or bottom of the drawer. The subject matter of this application can be used with any style of drawer attachment.
Neither of these styles are particularly easy to install, especially if one is trying to install the track to a cabinet that is already constructed and in place. It's fairly easy to attach the component of the system to the drawer itself since the drawer can be placed onto a workbench and the component placed so that it is parallel to the longitudinal axis of the drawer. It is much more difficult to place and attach the component attached to the cabinet itself. For the dry friction drawers, for example, there are two rails that need to be attached to the inside of the cabinet, and in order for the associated drawer to evenly rest on these rails, these rails need to be roughly parallel to the floor and substantially equidistant from the floor so that the weight of the drawer is distributed evenly across the rails. Therefore, for each rail attached to a cabinet wall, there must be at least two accurately placed points securing the rail to the cabinet. As both sides of a cabinet would require a rail, and each rail needs to be attached towards the front of the cabinet and towards the back of the cabinet so that the rails are secure and able to hold the drawer, an installer needs to accurately create at least four attachment points. In practice, to install a track of any design in a cabinet requires the installer to mark a first point of a track, and loosely attach the track to that point with a screw, then use a level to determine the placement of the second point of the track and reach to the back of the cabinet to drill a hole for the rear attachment screw and then screw the track into place. Once that side is attached, the installer needs to use a square or a level in conjunction with a straight-edge to mark the position of the track on the other side of the cabinet and drill and screw the second set of tracks into place. Assuming the four attachment points attaching the two rails to the inside of the cabinet are properly placed, then the drawer is ready to be placed within the cabinet. If the complementary tracks on the drawer do not properly align with the tracks installed on the cabinet one or more of the tracks will need to be removed, remeasured, and reattached so they do properly align.
Other designs may incorporate sliding rails or tracks that attach to the side or bottom of a drawer, but these other designs still need to be accurately placed within the cabinet and this placement is made easier by the subject matter of this application.